The defect of biodefense mechanisms in bovine leukocyte adhesion deficiency syndrome (BLAD) as observed from signal transduction pathway

从信号转导途径观察牛白细胞粘附缺陷综合征（BLAD）生物防御机制的缺陷

基本信息

批准号：
09460133
负责人：
KUWABARA Mikinori
金额：
$ 9.28万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

This project was performed to clarify the signal transduction mechanisms for NADPH oxidase activation and phagocytotis by using normal neutrophils and those with bovine leukocyte adhesion deficiency (BLAD) which was genetic deficient in beta2-integrin CR3 corresponding to the receptor of complement iC3b. Various reagents to inhibit NADPH oxidase-related signal transduction were used for this purpose. We found that inhibitors of protein kinase C (PKC), phosphatidyl inositol 3-kinase (PI 3-kinase) and p38 mitogen-activated protein kinase (p38 MAPK) were dose-dependently inhibited superoxide generation from serum-opsonized zymosan (s-OZ)-stimulated neutrophils from BLAD and normal calves, although stimulation of BLAD neutrophils with s-OZ brought about the lower generation of superoxide than that of normal neutrophils with s-OZ.These results indicated that the lack of beta2-integrin CR3 did not influence signal transduction pathways of NADPH oxidase but reduced superoxide production of NA … More DPH oxidase. This reduced NADPH oxidase activity in BLAD was partially recovered by transfusion of CD 18-positive granulocytes to diseased calf. Furthennore, PI 3-kinase and p38 MAPK but not PKC were shown to be required for phagocytotic activity in normal neutrophils. Concerning the intracellular mechanisms of NADPH oxidase activation, the p47phox, one component of NADPH oxidase, is known to be extensively phosphorylated at serines that are located among its C-terminal region and the phosphorylation is a trigger for the activation of NADPH oxidase. Using site-directed mutagenesis of p47phox and p47phox-deficient B cells from human chronic granulomatous disease (CGD), it was shown that the phosphorylation of serines 303/304, 359/370 and possibly serine 379 must take place in order to activate the oxidase. These results seem to be important in not only understanding the signal transduction mechanism of NADPH oxidase activity but also development for therapy of BLAD and p47phox-deficient CGD by the granulocyte or gene transfusion. Less

该项目旨在通过使用正常中性粒细胞和具有补体 iC3b 受体对应的 β2-整合素 CR3 遗传缺陷的牛白细胞粘附缺陷 (BLAD) 的中性粒细胞来阐明 NADPH 氧化酶激活和吞噬作用的信号转导机制。抑制 NADPH 氧化酶相关信号转导用于此目的，我们发现蛋白激酶 C (PKC) 抑制剂，磷脂酰肌醇 3-激酶 (PI 3-激酶) 和 p38 丝裂原激活蛋白激酶 (p38 MAPK) 剂量依赖性地抑制来自 BLAD 和正常小牛的血清调理酵母聚糖 (s-OZ) 刺激的中性粒细胞的超氧化物生成，尽管刺激BLAD中性粒细胞与s-OZ相比，超氧化物的产生量低于正常细胞这些结果表明，β2-整合素 CR3 的缺乏不会影响 NADPH 氧化酶的信号转导途径，但会减少 NA DPH 氧化酶的超氧化物产生，这种减少的 BLAD 中 NADPH 氧化酶活性可通过输注 BLAD 部分恢复。显示了患病小牛的 CD 18 阳性粒细胞、PI 3-激酶和 p38 MAPK，但未显示 PKC。关于 NADPH 氧化酶激活的细胞内机制，p47phox（NADPH 氧化酶的一种成分）已知在位于其 C 末端区域的丝氨酸处被广泛磷酸化，并且磷酸化是正常中性粒细胞吞噬活性所必需的。使用 p47phox 和的定点诱变触发 NADPH 氧化酶的激活。来自人类慢性肉芽肿病 (CGD) 的 p47phox 缺陷 B 细胞，显示丝氨酸 303/304、359/370 和可能的丝氨酸 379 必须发生磷酸化才能激活氧化酶。这些结果似乎很重要。不仅了解NADPH氧化酶活性的信号转导机制，还开发BLAD和p47phox缺陷的治疗方法CGD 由粒细胞或基因输注较少。